When you look at your meals, some ingredients (原料) are easy to see. But your meals are also filled with ingredients you can’t see.
Salt is a perfect example of an ingredient that you might not notice, even when you eat a lot of it. But it’s the salt we can’t see that concerns scientists most. For years, doctors have warned patients that too much salt can be bad for their health. Heart trouble has long been considered a grown-up problem. New research suggests that salt is starting to affect kids. And salt isn’t the only cause of high blood pressure. Eating lots of junk food, weighing too much and exercising too little also contribute to high blood pressure.
As part of the studies, hundreds of adults ate exactly what researchers told them to. These studies lasted for months at a time. The results showed a large drop in blood pressure in people who ate extra fruits and vegetables, lots of whole grains, low-fat dairy products (奶制品) and only small amounts of red meat. Eating well, the researchers concluded, is good for your heart. What’s more, studies from around the world show that high blood pressure and heart disease rates are lowest in the places where people eat the least amount of salt and lots of vegetables.
The best way to reduce the amount of salt you take, researchers say, is to make changes gradually. Start by dropping half as much salt in your dinner as you normally do. Switch to fresh foods instead of canned and bottled ones. “Kids today need to give salt the shake,” says David Grotto, a doctor in Chicago, “in order to keep healthy.”
28. It can be concluded from the first two paragraphs that .
A. meals are filled with lots of healthy ingredients.
B. some hidden ingredients affect people’s health.
C. eating too much salt leads to overweight.
D. children eat more salt than adults do.
29. According to the third paragraph, the studies examined the relationship between .
A. eating and diseases B. heart trouble and age
C. salt and the daily life D. blood pressure and health
30. How can people avoid suffering heart disease?
A. By taking more exercise. B. By stopping eating salt at times.
C. By losing weight at an early age. D. By eating healthily.
31. What is the purpose of the passage?
A. To encourage people to take more exercise. B. To give advice on how to cook healthy food.
C. To persuade people to take less salt. D. To show the results of the studies.